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1. CCTS and CCTS:CQD nanocomposites were successfully deposited. 2. Physical characteristics of synthesized CCTS and CCTS:CQD thin films were examined. 3. CCTS:CQD nanocomposite was used as a p-type layer in an inorganic thin-film solar cell. 4. The photoconversion efficiencies were obtained for CCTS and CCTS:CQD nanocomposite.

In the current investigation, it was focused mainly to compare and evaluate the analytical and experimental trials on the cutting temperature in machining the titanium alloy using micro-hole textured cutting inserts. Initially, the main input parameters such as cutting speed, depth of cut, and feed rate have been used to evaluate the performances. Box–Behnken technique of response surface methodology was used to perform machining experiments. Secondly, with the help of width of cut and thickness of the chip formed at each trial, the analytical calculation of cutting temperature at the two-deformation zone, namely primary and secondary of the orthogonal cutting, has been done. The efficacy of the input parameters on cutting temperatures has been also compared with the analytical calculation. Importance of the cutting parameters was studied with the help of mean effective plots. Results also revealed that the deviation of cutting temperature between the numerical and experimental investigation was only 13%. This depicts the analytical formulation which was much close relation to that of machined trials of cutting temperatures. Further, the cutting temperatures are found to be minimized at lower feed rates and cutting speed using the observation of mean effect plots.

The primary goal of this work is to examine the effect of in situ substrate conditions viz., substrate bias voltage and substrate temperature on the structural, morphological, compositional, and mechanical properties of co-sputtered Ni Ti alloy thin films. Application of substrate bias voltage during deposition creates defect sites which facilitate the growth of nano-crystalline Ni Ti films by imposing restriction on the coalescence of neighboring grains which has lead to interesting properties. Glancing Incidence X-ray diffraction studies revealed the co-existence of B2 and B19′ crystal structures and thus possess potential for martensitic phase transformation, which is the prerequisite for shape memory behavior. Thermally-induced martensitic twin bands were observed within the nano-grains with high-resolution transmission electron microscopy. Surface elemental composition was investigated by X-ray photoelectron spectroscopy to understand the chemical state of Ni Ti thin films. Differential scanning calorimetric measurements confirms the martensitic transformation below room temperatures. Nanoidentation studies have shown higher hardness values for Ni Ti films processed at high substrate temperature when compared to the film deposited under the influence of bias voltage due to the deformation mechanism governed by grain boundary absorption of the localized strain in nanometer scale.

To date, there is no ideal anti-reflection (AR) coating available on solar glass which can effectively transmit the incident light within the visible wavelength range. However, there is a need to develop multifunctional coating with superior anti-reflection properties and self-cleaning ability meant to be used for solar glass panels. In spite of self-cleaning ability of materials like TiO2 and ZnO, these coatings on glass substrate have tendency to reduce light transmission due to their high refractive indices than glass. Thus, to infuse the anti-reflective property, a low refractive index, SiO2 layer needs to be used in conjunction with TiO2 and ZnO layers. In such case, the optimization of individual layer thickness is crucial to achieve maximum transmittance of the visible light. In the present study, we propose an omni-directional anti-reflection coating design for the visible spectral wavelength range of 400–700 nm, where the maximum intensity of light is converted into electrical energy. Herein, we employ the quarter wavelength criteria using SiO2, TiO2 and ZnO to design the coating composed of single, double and triple layers. The thickness of individual layers was optimized for maximum light transmittance using essential Mcleod simulation software to produce destructive interference between reflected waves and constructive interference between transmitted waves.

Ti-6Al-4V alloy is well known for its difficulty in machining due to its ultimate hardness. The temperature generated at the tool-chip interface is typically high which results in poor surface finish and rapid tool wear. The current focus of work was to analyze the influence of response parameters such as cutting speed, feed rate and depth of cut on the surface roughness on the non-textured and textured cutting inserts. Response Surface Methodology (RSM) was utilized to generate the analytical relation between the process parameters and their interaction with the responses namely surface roughness. Analysis of Variance (ANOVA) was implemented to correlate with the significant factors and the correctness of the model. The machining was done experimentally using the textured and non-textured tools and the surface roughness was measured to analyze the influence of process parameters. It was found that the surface roughness was immensely reduced while using microtextured cutting tools.

A new anti-reflection coating based on amorphous barium titanate (a-BTO) was developed using RF magnetron sputtering technique. Systematic studies on the structural and optical properties were carried on a-BTO thin films deposited on polished Si and textured Si substrates. In the visible range of the solar spectrum, the refractive index was found to be 2.02-1.91 with high transmittance of greater than 85%. Maximum reduction in the reflectance for a-BTO on polished Si and textured Si substrates was found to be 100% (at 550 nm) and 85% (at 400 nm), respectively. Further, improvement in cell efficiency of a Si solar cell with a-BTO anti-reflection coating was found with an increase from 9.3% to 10% accompanied by improvements in overall performance parameters such as short circuit density (J(sc)), open circuit voltage (V-oc) and fill factor (FF). These results indicate that an a-BTO thin film deposited using RF magnetron sputtering can be used as an alternative anti-reflection coating for Si based photovoltaic cells.

Copper Zinc Tin Selenide (CZTSe) absorber films were obtained by growing CZT films with simultaneous RF and DC magnetron sputtering followed by thermal evaporation of Selenium. The deposition of CZTSe films was performed with different sputter powers with in-situ and post annealing of the deposited films at 400 °C in order to get uniformity and phase purity. Detailed GIXRD analysis concluded that a phase pure CZTSe film was obtained for in-situ annealed sample with Cu-Sn deposited through RF sputter power of 250W and Zn deposited through pulsed DC power of 200W. In conclusion from Raman scattering measurements, phase pure Raman active A mode of Kesterite CZTSe was observed for the same sample. Compositional analysis by EDS and XPS clearly showed that the CZTSe films are having Cu poor and Zn rich composition, favoring shallow Cu-vacancy which is highly desirable as p-type absorber layers for solar cells. The optical bandgaps (Eg) of the films calculated using Tauc plots were within the reported bandgap value of 1.0–1.35eV. The present deposition approach using hybrid PVD tool helps to control individual fluxes (Cu-Sn, Zn, Se), more precisely without the need of extra selenization step, leading to one step reduction in production process.